1. Field of the Invention
The field of this invention relates generally to testing and treating tools which may be run into the well on a well string or a drill string and which includes a packer assembly incorporating one or more, and generally more, elements which are spaced and can be expanded by manipulation of the well string or drill string on which the tool is run into the well bore so that the packer element or packer elements may be sealingly engaged with the well bore wall and isolate a zone therein for conducting tests or treatment.
2. Description of the Prior Art
The prior art is generally constructed as above described, but with the packer elements being of the inflatable type. Prior to this invention, it was apparently not considered generally feasible or practical to employ squeeze packer elements in a testing or treating well tool of the type to which the present invention relates.
Further, so far as known to Applicant, the prior art discloses no arrangement for maintaining the expanded elements, inflatable or squeeze, in position with the well bore wall under varying pressure circumstances that might occur during use of the tool. In some circumstances, varying pressure conditions have caused the packer elements to move or creep along the well wall when sealingly engaged therewith. Also, the prior art testing apparatus such as shown in U.S. Pat. No. 3,439,740 issued to G. E. Conover shows a construction employing inflatable elements which are expandable by a pump incorporated in the tool which is actuated by rotation of the pipe string or drill string that extends from the earth's surface and on which the tool is supported. In U.S. Pat. No. 4,320,800, issued to James M. Upchurch, one of the inflatable packer elements is inflated by rotation of the pipe string and the other inflatable packer element is inflated in response to upward and downward movement of the pipe string.